Interlocked selection control apparatus

ABSTRACT

Apparatus especially useful for vending selection control. A plurality of triggerable semi-conductor current switching devices are provided for selectively energizing a plurality of vend control means each causing the dispensing of a respective article. The switching devices are triggered by respective ones of selector switches which draw current through a source having a predetermined source impedance. A respective diode connects each of the switching devices to the source so that conduction through any one of the devices immediately shunts the source thereby preventing triggering of any of the other devices, preventing selection of more than one article for each vend operation.

United States Patent Hendrickson et a1.

[54] INTERLOCKED SELECTION CONTROL APPARATUS [72] Inventors: William M.Hendrickson, St. Louis; Patrick J. Davis, Plorissant, both of Mo.

[73] Assignee: UMC Industries, Inc., NY.

[22] Filed: Sept. 1, 1971 [21] Appl. No.: 176,855

New York,

9/1970 Haolicek ..317/l48.5 B 8/1967 Schuller et al ..194/l0 PrimaryExaminer-J. D. Miller Assistant Examiner-l-larry E. Moose, Jr.

[57] ABSTRACT Apparatus especially useful for vending selection control.A plurality of triggerable semi-conductor current switching devices areprovided for selectively energizing a plurality of vend control meanseach causing the dispensing of a respective article. The switchingdevices are triggered by respective ones of selector switches which drawcurrent through a source having a predetermined source impedance. Arespective diode connects each of the switching devices to the source sothat conduction through any one of the devices immediately shunts thesource thereby preventing triggering of any of the other devices,preventing selection of more than one article for each vend operation.

8 Claims, 1 Drawing Figure [56] References Cited UNITED STATES PATENTS3,596,111 7/1971 l-lan ..317/137 PRB D.C. SOURCE T 4 a 4 oc. GROUND I\=A.C, SOURCE 2o N=A.Q NEUTRAL l' INTERLOCKED SELECTION CONTROLAPPARATUS BACKGROUND OF THE INVENTION This invention relates toselection control apparatus for selecting only one of a variety ofcontrol responses, i.e., interlocked selection control, and moreparticularly to vending selection control apparatus for causingdispensing of only one selected article from a variety of articles.

In vending machine operation, it is important to provide protectionagainst a purchaser obtaining more than one article during a vendoperation. In addition, it may be necessary to permit selection ofarticles at different prices, it being important that an article not bedispensed unless there has been insertion of a sufficient amount ofcoin. In such machines, however, it may be desired to permit changing ofthe price associated with a selector or to permit changing of the totalnumber of possible selections.

SUMMARY OF THE INVENTION Among the several objects of the invention maybe noted the provision of selection control apparatus; the provision ofsuch control apparatus for causing only one selected control responsefrom a variety of available control responses; the provision of suchcontrol apparatus especially adapted for vending control; the provisionof such vending control apparatus providing positive protection againstobtaining more than one article during a vend operation; the provisionof such vending control apparatus permitting selection of articles atdifferent prices and permitting vending of an article onlyafterinsertion of a sufficient amount of coin; the provision of suchvending control apparatus readily permitting changing of the priceassociated with a selector; the provision of such vending controlapparatus facilitating changing of the total number of possibleselections; and the provision of such vending control apparatus which isprimarily electronic in character, and which is reliable andlong-lasting in operation. Other objects and features will be in partapparent and in part pointed out hereinafter.

Briefly, selection control apparatus of the invention as used forvending control is adapted for causing dispensing of only one selectedarticle from a variety of available articles after the price of saidselected article is deposited. The apparatus includes a plurality ofelectromagnetic vend control means each, when energized,

being adapted to cause the dispensing of a respective article. Arespective plurality of triggerable semiconductor current switchingdevices is provided for selectively energizing the vend control means,there being a source means for providing current for triggering thedevices and which has a predetermined source impedance. Means isresponsive to the deposit of money for connecting this current source tothose of a plurality of terminals corresponding to different prices forwhich the amount of money deposited at least equals the respectiveprice. Diode means connects each of the switching devices to thatterminal which corresponds to the price of that respective article.Manually operable selection switch means applies current from the sourceto a selected one only of the switching devices thereby to trigger thisone device into conduction when the one device is connected to aterminal to which current is provided from the source. Conductionthrough this device immediately shunts the source through the respectivediode means thus preventing triggering of any of the other of saiddevices. One side of each of the vend control means is connected to arespective one of said devices, while electromagnetic relay meansresponsive to conduction through any of the devices applies a voltage tothe other sides of the vend control means. A vend control meansconnected to a triggered one of the devices is thereby energized bycurrent conducted through the respective device, causing the respectivearticle to be dispensed. Dispensing of all other articles is preventedby the shunting of the source.

BRIEF DESCRIPTION OF THE DRAWING The single FIG. is a schematic circuitdiagram of selection control apparatus of the invention as utilized forvending control purposes.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing,ac. and dc. source connections and their respective ground or neutralconnections for a control of the invention are identified by symbols asshown in the legend accompanying the figure.

A coin handling mechanism is used with the control but forms no part ofthe present invention. A brief description of certain of its elementsand their operation is necessary for an understanding of the overallmerchandiser apparatus. Reference may be made to coassigned U.S. Pat.No. 3,335,838 for full details of a coin handling mechanism such as maybe used. Briefly, the coin handling mechanism includes a coin handlingor reset motor Ml which is operative to reset the coin handlingmechanism, e.g., after it has been advanced by the deposit of coins andafter a vend cycle has been initiated. Operation of motor M1 isinitiated by closure of a delivery switch DS upon the vending of aselected article. This motor controls two cam driven switches 81 and S2which are closed during the reset cycle. Switch S1 provides a holdingcircuit for the motor Ml itself and switch S2 is employed in completinga vend cycle as described hereinafter.

The coin handling mechanism also includes a socalled recorder ortotalizer mechanism RCDR which, as described in the aforesaid U.S. Pat.No. 3,335,838, comprises a form of stepping switch mechanism forprogressively connecting a control lead CL2 to selected ones of aplurality of price lines Pl-P20 as money is deposited in the coinhandling mechanism. Only six of the price lines are shown to conservedrawing space but typically 20 lines might be employed to permit a rangeof 20 different prices to be accommodated, e.g.,from 5 to $1.00. Therecorder RCDR may, if desired, be of the type which connects ones of theprice leads with a plurality of change leads controlling change-makingapparatus of a known type to cause refunding of change if the amount ofcoin deposited is greater than the price of a selected article. Therecorder RCDR is adapted to be reset through operation of reset motorM1.

Indicated at SS1 (A-J) are a plurality of selection solenoids, onlythree of which are shown to conserve space in the drawing. The operatingwindings of these solenoids are shunted by respective suppression diodesDS for suppressing inductive surges upon deenergization. Energization ofone of the selection solenoids SS1 (A-J is adapted to cause thedispensing of a respective article. In place of these solenoids, othertypes of control response means (such as motors, etc.) may be used. Oneside of each of the selection solenoids SS1 is connected to a commoncontrol lead CLl. The other end of each solenoid is connected to groundthrough a respective isolation diode D1 (A-J), a respective SCR Q1 (A-J)and a respective bias diode D2 (A-J). Each bias diode is forward biasedby current provided through a respective bias resistor R1 (A-J). Theanode of each SCR is shunted by a suppression network comprising aresistor R3 (A-J) and a capacitor C1 (A-J). The gate electrode of eachSCR is bypassed to its cathode through a capacitor C2 (A-J) and isbiased to ground through a resistor R4 (A-J). Triggering current can beapplied to the gate of each SCR through a respective article selectionswitch SW1 (A-J) and a respective current limiting resistor R5 (A-J).The switches SW1 (A-J are connected in series to provide exclusiveoperation. v

The anode of each SCR Q1 (A-J) is connected, through a respective diodeD3 (A-J), to a price board PRB. The price board PRB is a matrix switchwhich allows any one of the SCR anode leads to be connected to any oneof the price leads (PLl-PL20) and which permits more than one SCR anodelead to be connected to any one of the price leads. Thus each SCR anodelead can be connected to that price lead which corresponds to the priceof the item to be vended.

A relay RY is provided whose operation is generally to control theenergization of the selection solenoids and, when energized, closes aset of contacts RYK to supply the dc source voltage to control lead CLl.One side of relay RY is connected to control lead CL2 and the other sideis supplied with the d.c. source potential.

As is described in greater detail hereinafter, current drawn throughresistor R6 is provided to the select switches SW1 (A-J) through acircuit which includes a Zener diode Z1, a further resistor R7, and agate supply lead designated GSL. Lead GSL is interconnected withcam-operated switch S2, the latter being connected, when closed, forgrounding lead GSL.

The junction between resistor R6 and Zener diode Z1 is designatedjunction A in FIG. 1 and is connected through an isolating diode D4 to apoint in the circuit or junction designated B. Junction B is connectedby control lead CL2 to that one of price leads P1-P20 which correspondsto an exact match between the amount deposited and the price of an itembeing purchased.

Considering now its operation, the control circuit is illustrated in itsnormal or ready operating condition, that is, energized but prior to thedeposit of any money. The normal operation of the merchandiser from thiscondition is then substantially as follows: The deposit of money in thecoin handling mechanism causes the recorder RCDR to progressively shiftcontrol lead CL2 to the price lead PLl-PLZO in conventional manner sothat, at each step, a price lead is connected corresponding to the totalamount of coin deposited. Prior to the making of a selection, thepotential at the points A and B is substantially above ground potentialand current is available therefrom. Thus current can be drawn throughthe gate supply lead GSL from resistor R6. Accordingly, operating anyone of the selection switches SW1 (A-J) will cause triggering current tobe applied to the gate of the respective SCR Q1 (A-J).

Assuming that the selection is a proper one and that the anode of thetriggered SCR is therefore connected through the price board PRB to oneof the price leads PLl-PL20, anode current will be available to thetriggered SCR through the resistor R6. Thus, the selected SCR willswitch into its conducting state in the manner understood by thoseskilled in the art. As is also understood by those skilled in the art,conduction in this SCR will continue even though the triggering currentis withdrawn from the gate of the SCR. The selection SCR is thus in asense latched into the conducting state.

It should be noted that the existence of a path of conduction through aselection SCR does not immediately energize the respective selectionsolenoid SS1 (A-J) since the contacts RYK are open and thus no currentis available through the control lead CLI. Conduction through thetriggered SCR will, however, cause the voltage at the junction B toimmediately drop substantially to ground potential since this conductioneffectively shunts the source of gate triggering current causing thesupply voltage to be dissipated across the resistor R6 which presents acontrolled or predetermined source impedance to the gate supply leadGSL. Assuming that a proper selection is made and that junction B isthus pulled substantially to' ground potential, current flow throughresistor R6 is diverted from the gate supply lead GSL by conductionthrough diode D4. The Zener diode Z1 offsets any residual voltage at thejunction B caused by forward voltage drops the various semi-conductorjunctions in the conduction path and thus substantially all voltage isremoved from the gate supply lead GSL. With the source of triggeringcurrent thus cut off, no other selection can be made. It should be notedthat this action occurs as quickly as the selected SCR 0] (A-J) can turnon, i.e., in the order of a few microseconds, and does not depend uponthe relatively slow operation in any electromechanical element. Thus,triggering of an SCR occurs in much less time than is required totransfer the contacts of another of the selector switches SW1 (A-J).

In addition to cutting off the source of current for triggering theselection SCRs, the dropping of junction B substantially to groundpotential applies a voltage across the operating winding of relay RYwhich is thereby energized. The consequent closing of the contacts RYKthereby applies current to the control lead CLl. When current isprovided at lead CLl, the selection solenoid SS1 (A-J) corresponding tothe triggered selection SCR Q1 (A-J) is energized since the voltage atthe anode of that SCR is maintained substantially at ground potential byconduction through the SCR. The diodes D1 (A-J) and D3 (A-J prevent anyinteraction between the solenoids. Energization of the respectiveselection solenoid causes selected articles to be vended or dispensed.

Upon delivery of the selected article, delivery switch DS closes toenergize and thus initiate operation of motor M1. Upon rotation of motorMl, switch S1 closes to maintain energization of the motor to ensurethat it completes a full cycle. Switch S2 also closes causing groundingof the gate supply lead GSL thereby to prevent triggering of one of theSCRs Q1 (A-J) during resetting of the recorder or totalizer RCDR.Continued operation of motor M1 resets the recorder thereby opening thecircuit between junction B through control lead CL2 to the triggeredselection SCR. Junction B then returns to the dc. supply potential andrelay RY is accordingly deenergized, permitting its contacts RYK toopen. As a result, the selection solenoid which had been energized isnow deenergized. Since no potential is now supplied to any of the SCRsQ1 (A-J), the triggered SCR is thereby commutated and hence becomes onceagain non-conductive. At the completion of its cycle, motor M1 causesswitches S1 and S2 to return to their normally-open conditions and motorMl thereby stops. The apparatus is then ready for a new vend cycle.

In view of the above, it will be seen that the several objects of theinvention are achieved and other advantageous results attained.

As various changes could be made in the above constructions withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawing shall be interpreted as illustrative and not in a limitingsense.

WHAT IS CLAIMED IS:

1. Selection control apparatus for causing only one selected controlresponse from a variety of available control responses, said apparatuscomprising:

a plurality of control response means each of which, when energized,causes a respective control response;

a respective plurality of triggerable semiconductor current switchingdevices;

source means for providing current for triggering said devices, saidsource means having a predetermined source impedance;

manually operable selector means for applying current from said sourceto a selected one only of said devices thereby to trigger said onedevice into conduction;

a respective diode means connecting each of said switching devices tosaid source whereby conduction through any one of said devicesimmediately shunts said source thereby preventing triggering of any ofthe other of said devices; and

circuit means interconnecting each of said control response means with arespective one of said devices for energization of that control responsemeans by current conducted through the respective device wherebytriggering of one of said devices causes a respective control responseand prevents any other of the available control responses.

2. Selection control apparatus as set forth in claim 1 wherein each ofsaid control response means comprises a solenoid.

3. Selection control apparatus as set forth in claim 1 wherein saidtriggerable semi-conductor current switching devices are siliconcontrolled rectifiers.

4. Selection control apparatus as set forth in claim 1 wherein saidsource means includes a resistor providing sai det rmined source imedance.

eiecti on control appara us as set forth in claim 1 wherein saidselector means comprises a plurality of double-throw switches which areconnected in series through one side of each of said switches, the otherside of each switch being connected to a respective one of said currentswitching devices thereby to provide triggering current to said onedevice exclusively.

6. Vending selection control apparatus for causing dispensing of onlyone selected article from a variety of available articles after theprice of said selected article is deposited, said apparatus comprising:

a plurality of electromagnetic vend control means each of which, whenenergized, is adapted to cause the dispensing of a respective article;

a respective plurality of triggerable semiconductor current switchingdevices for selectively energizing said vend control means;

source means for providing current for triggering said devices, saidsource means having a predetermined source impedance;

a plurality of terminals corresponding to different prices;

means responsive to the deposit of money for connecting said currentsource to those terminals for which the amount of money deposited atleast equals the respective price;

isolation means connecting each of said devices to that terminal whichcorresponds to the price of that respective article;

manually operable switch means for applying current from said source toa selected one only of said devices thereby to trigger said one deviceinto conduction when said one device is connected to a terminal to whichcurrent is provided from said source, conduction through said one deviceimmediately shunting said source through the respective isolation meansthereby preventing triggering of any of the other of said devices;

circuit means connecting one side of each of said vend control means toa respective one of said devices; and

means responsive to conduction through any of said devices for applyinga voltage to the other sides of said vend control means whereby a vendcontrol means connected to a triggered one of said devices is energizedby current conducted through the respective device to cause therespective article to be dispensed and whereby dispensing of all otherarticles is prevented by the shunting of said source.

7. Vending selection control apparatus as set forth in claim 6 whereinsaid isolation means comprises a plurality of diodes respectivelyconnected with each of said devices.

8. Vending selection control apparatus as set forth in claim 6 whereinsaid means responsive to conduction through any of said devicescomprises electromagnetic relay means connected in a circuit with saidsource and said means responsive to the deposit of money.

1. Selection control apparatus for causing only one selected controlresponse from a variety of available control responses, said apparatuscomprising: a plurality of control response means each of which, whenenergized, causes a respective control response; a respective pluralityof triggerable semiconductor current switching devices; source means forproviding current for triggering said devices, said source means havinga predetermined source impedance; manually operable selector means forapplying current from said source to a selected one only of said devicesthereby to trigger said one device into conduction; a respective diodemeans connecting each of said switching devices to said source wherebyconduction through any one of said devices immediately shunts saidsource thereby preventing triggering of any of the other of saiddevices; and circuit means interconnecting each of said control responsemeans with a respective one of said devices for energization of thatcontrol response means by current conducted through the respectivedevice whereby triggering of one of said devices causes a respectivecontrol response and prevents any other of the available controlresponses.
 2. Selection control apparatus as set forth in claim 1wherein each of said control response means comprises a solenoid. 3.Selection control apparatus as set forth in claim 1 wherein saidtriggerable semi-conductor current switching devices are siliconcontrolled rectifiers.
 4. Selection control apparatus as set forth inclaim 1 wherein said source means includes a resistor providing saidpredetermined source impedance.
 5. Selection control apparatus as setforth in claim 1 wherein said selector means comprises a plurality ofdouble-throw switches which are connected in series through one side ofeach of said switches, the other side of each switch being connected toa respective one of said current switching devices thereby to providetriggering current to said one device exclusively.
 6. Vending selectioncontrol apparatus for causing dispensing of only one selected articlefrom a variety of available articles after the price of said selectedarticle is deposited, said apparatus comprising: a plurality ofelectromagnetic vend control means each of which, when energized, isadapted to cause the dispensing of a respective article; a respectiveplurality of triggerable semiconductor current switching devices forselectively energizing said vend control means; source means forproviding current for triggering said devices, said source means havinga predetermined source impedance; a plurality of terminals correspondingto different prices; means responsive to the deposit of money forconnecting said current source to those terminals for which the amountof money deposited at least equals the respective price; isolation meansconnecting each of said devices to that terminal which corresponds tothe price of that respective article; manually operable switch means forapplying current from said source to a selected one only of said devicesthereby to trigger said one device into conduction when said one deviceis connected to a terminal to which current is provided from saidsource, conduction through said one device immediately shunting saidsource through the respective isolation means thereby preventingtriggering of any of the other of said devices; circuit means connectingone side of each of said vend control means to a respective one of saiddevices; and means responsive to conduction through any of said devicesfor applying a voltage to the other sides of said vend control meanswhereby a vend control means connected to a triggered one of saiddevices is energized by current conducted through the respective deviceto cause the respective article to be dispensed and whereby dispensingof all other articles is prevented by the shunting of said source. 7.Vending selection control apparatus as set forth in claim 6 wherein saidisolation means comprises a plurality of diodes respectively connectedwith each of said devices.
 8. Vending selection control apparatus as setforth in claim 6 wherein said means responsive to conduction through anyof said devices comprises electromagnetic relay means connected in acircuit with said source and said means responsive to the deposit ofmoney.